Wound Man is an illustration which first appeared in European surgical texts in the Middle Ages.
It laid out schematically the various wounds a person might suffer in battle or in accidents
I had to share this beautiful medical illustration by Tess Tobolic. Sometimes I regret not pursuing a similar path.
Tree-barking of the aorta
Before rupture occurs, infamous ‘tree bark’ grooves appear on the inner layer of the aorta.
They are basically stretch marks of the aorta and can be seen in cases of Marfan-style dilatation of the aortic root. The reason you can’t see them in cases of atherosclerosis is because the markings are masked by plaques.
A corrected reticulocyte count <3 % indicates underproduction of RBCs.
Being in love
is a disease
You get underproduction
Syphilitic Aortic Aneurysm
Syphilitic aortitis is an inflammatory disease of the aorta associated with the tertiary stage of syphilis infection. SA begins as inflammation of the adventitia (outer layer), including the blood vessels that supply the aorta itself with blood, the vasa vasorum. As SA worsens, the walls of the vasa vasorum thicken, restricting blood flow and causing ischemia of the outer two-thirds of the aortic wall. Starved for oxygen and nutrients, elastic fibres become patchy and smooth muscle cells necrose. The wall weakens and scars. If the disease progresses, syphilitic aortitis leads to an aortic aneurysm.
Atherosclerosis of a coronary artery
Shown is a typical eccentric atherosclerotic plaque. A central necrotic core shows dystrophic calcification. Note the fibrous cap and that the media is thinned throughout most of the circumference.
Atherosclerosis is characterised by intimal lesions called atheromas that protrude into vessel lumens. An atheromatous plaque consists of a raised lesion with a soft, yellow core of lipid (mainly cholesterol and cholesterol esters) covered by a white fibrous cap. In addition to mechanically obstructing blood flow, atherosclerotic plaques can rupture, leading to catastrophic vessel thrombosis; plaques also weaken the underlying media and thereby lead to aneurysm formation.
Key steps of pathogenesis:
Endothelial injury, which causes increased vascular permeability, leukocyte adhesion, and thrombosis
Accumulation of lipoproteins (mainly LDL and its oxidized forms) in the vessel wall
Monocyte adhesion to the endothelium, followed by migration into the intima and transformation into macrophages and foam cells
Factor release from activated platelets, macrophages, and vascular wall cells, inducing smooth muscle cell recruitment, either from the media or from circulating precursors
Smooth muscle cell proliferation
Lipid accumulation both extracellularly and within cells (macrophages and smooth muscle cells)
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Rickets is a disorder caused by a lack of vitamin D (most commonly), calcium, or phosphate. It leads to softening and weakening of the bones.
Vitamin D is a fat-soluble vitamin absorbed from food or produced by the skin when exposed to sunlight.
Causes of vitamin D deficiencies may be due to:
Lack of exposure to sunlight
Insufficient dietary intake of vitamin D
Malabsorption of vitamin K (often due to disorders which reduce digestion/absorption of fats).
Hereditary rickets is a form of the disease that is passed down through families. It occurs when the kidneys are unable to hold onto the mineral phosphate.
Rickets may occur in children who have disorders of the liver or who cannot convert vitamin D to its active form.
Painful, tender bones and muscle cramps
Increased bone fractures
Skeletal deformities, including:
- Asymmetrical or odd-shaped skull
- Bumps in the ribcage (rachitic rosary)
- Breastbone pushed forward (pigeon chest)
- Pelvic deformities
- Spine deformities (including scoliosis or kyphosis)
The above image shows a coloured X-ray of pulmonary tuberculosis, caused specifically by the bacterium Mycobacterium tuberculosis.
TB is most commonly caused by the bacterium Mycobacterium tuberculosis (MTB), which is spread by droplet infection (transmitted in saliva, usually by coughing or sneezing). MTB is highly aerobic, requiring high levels of oxygen. It affects the respiratory system, particularly damaging and destroying lung tissue.
Only about 30% of people exposed to TB will become infected. This is much more likely to occur in individuals who are immunocompromised (hence TB often presenting itself in those whom are HIV positive).
The primary infection of TB is often asymptomatic, although occasionally it may cause fever and/or a dry cough. In an individual with a healthy immune system, a localised inflammatory response will occur, forming a nodule of tissue called a tubercule (containing dead bacteria and macrophages). Typically (in about 90% of cases) the condition will resolve itself without the individual ever having known they were infected.
However MTB may survive, as alveolar macrophages are unable to digest the bacteria, allowing it to remain in a state of dormant latency and multiply silently. After a period of time, when the host’s immunity is compromised (for example, due to infection or malnourishment) the bacteria will produce active tuberculosis.
When the infection presents itself in this way (referred to as miliary tuberculosis), symptoms may initially include loss of appetite, fever, productive cough and loss of energy, loss of weight/anorexia or night sweats however these are very non-specific. As the infection progresses, one may develop tuberculous pleuritis (causing chest pain, nonproductive cough and fever), increase in production of mucous and haemoptysis (coughing up blood).
As the infection spreads it may lead to symptoms such as abdominal pain, painful urination, sterility and brain damage (depending on which areas are affected and to what extent).
Treatment and prevention:
If left untreated, TB will eventually cause death. This may be because of hypoxia (due to severe lung damage) or organ failure (due to malnutrition). Also, as TB disarms a critical part of the immune system, it makes patients much more susceptible to opportunistic infections (such as pneumonia) therefore patients are often treated with antibiotic medication outside of a hospital environment. Vaccines are commonly administered as a form of prevention and are effective against severe forms of paediatric TB however adult pulmonary TB is still prevalent (there are currently more TB cases worldwide than ever before).
An X-ray may indicate the presence of TB however other infections appear similar so cultures must be taken to confirm the diagnosis.
Today (03/24/12) is World TB Day
1 out of every 3 people in the world is infected by tuberculosis and 95% of cases occur in developing countries where medication is largely unavailable or unaffordable. In addition, it’s becoming more resistant to treatment and only one drug is currently in the third stage of clinical trials - no pharmaceutical company wants to put money into a drug that they can’t put a huge price tag on and more so, a drug that is only taken for a relatively short period of time and will also eventually become ineffective too. People are dying needlessly because they can’t get the treatment that they need.
Please take some time out of your day to inform yourself about this condition and raise awareness to others. Just like the progress we are making with HIV treatment and prevention in developing countries, we can make a difference and there can be change.
Histology Project I
These are all images of human cells and tissues.
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A personal favourite from Gray’s Anatomy.
Scoliosis is the abnormal curvature of the spine to the sides.
80% of cases are idiopathic, meaning that they have no known cause. The remainder are due to neuromuscular disorders, including Marfan’s syndrome (disorder of connective tissues), muscular dystrophy (a condition causing muscle weakness) and cerebral palsy (a neurological condition caused by brain damage).
Treatment includes back braces, pain management and in extreme cases, surgical correction.